1. Field
The present disclosure relates to a field of mobile communication, and more particularly, to a method and an apparatus for controlling of a Downlink Data Notification (DDN) message, which can reduce the generation of DDN messages while a user equipment in an inactive (ECM-idle) state transits to an active (ECM-active) state.
2. Background
Recently, since technologies of communications, computer networks and semiconductor are rapidly developed, various services can be provided via wireless communication networks and consumer's demands for these services are increasing day by day. Further, the wireless internet service market is exploding around the world recently. Accordingly, services provided by mobile communication systems using such wireless communication networks are being developed to a voice service as well as a multimedia communication service for transmitting various data. Since use of smart phones and demand for data traffic are increasing, mobile communication companies are investing in facilities and techniques while considering loads and influences of systems so as to accommodate the increased data traffic in a variety of ways.
Long Term Evolution (LTE), which is a network for realizing requirements of a high data rate, low latency and packet-optimized radio access with respect to access networks, is devised to accommodate high-speed rich media while guaranteeing backward compatibility for the existing 3GPP/non-3GPP access networks. The LTE is an all-IP based network excluding the existing circuit-switched communication and enhances the efficiency of network resources by providing differentiated quality of service (QoS) for real-time services (e.g., a voice communication, a video communication, and the like) and non-real-time services (e.g., web browsing, Store and Forward data transmission, and the like) by means of strengthening of QoS management functions. In addition, the LTE extends bandwidth for wireless communication by adopting smart antenna techniques (i.e., Multiple Input Multiple Output (MIMO)).
An Evolved Packet Core (EPC) network, which is a core network of LTE, performs call processing for voice and data processing in order to provide a service through systematic operations between an eNB (eNodeB) and a Mobility Management Entity (MME), between the MME and a Serving Gateway (S-GW), and between the S-GW and a Packet Data Network-Gateway (P-GW). The EPC network recognizes control messages, such as call setup messages and call release messages, as an Internet Protocol Packet (IP packet), and transfers the control messages to the P-GW or receives the control messages from the P-GW and then transfers the control messages to a user equipment (UE).
If a bearer is established (active state, ECM-Active) to enable radio resources to be used in an LTE system and then the radio resources used for the bearer establishment are not used for a predetermined period of time, the radio resources used for the bearer establishment are released (inactive state, ECM-Idle) for the purpose of efficient use of the radio resources. When the radio resources used for the bearer establishment have been released and then a reception signal then exists for the UE using the corresponding bearer, the S-GW informs the MME of the reception signal through a Downlink Data Notification (DDN) message. At this time, the MME can inform the corresponding UE of the existence of the reception signal through a paging procedure. The corresponding UE transmits a service request message to the MME as a response to the DDN message, thereby requesting reconnection of the radio resources used for the bearer establishment. The UE frequently perform transitions between the active state and the inactive state in order to execute an application, where there is a problem in that a load occurs in EPC equipment since DDN messages are increased in proportion to the number of transitions of the UE.
The above references are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features and/or technical background.